Electronic communications between a sender and a receiver may include one or more levels of security or authentication, including confirming respective identities of the sender and receiver, and encrypting the data communicated between them. Some conventional methods use an ID and a password for authentication. Communications may be protected by encryption using public and private keys. However, when the ID and password are known by an unauthorized sender or receiver, an unauthorized access or an unauthorized communication is possible. Accordingly, it may be desirable to implement a communication protocol to protect an electronic system from an unauthorized access or use.